Methods and devices for 3D object measurement are sufficiently known. Thus, DE 197 04 496 C2, inter alia, describes a photonic mixer device (PMD) which can be used for measuring passive objects. The photonic mixer device contains a p-doped silicon substrate, on which at least two light-sensitive modulation photogates are arranged. Accumulation gates likewise arranged on the p-doped silicon substrate are assigned to the modulation photogates. The modulation photogates are operated with a modulating push-pull voltage. Intensity-modulated light incident on the p-doped silicon substrate generates minority charge carriers which drift under the influence of the modulating push-pull voltage to the accumulation gates, where they are integrated. A prerequisite for an object measurement is that a predefined phase relationship exists between the phase of the push-pull voltages and the phase of the intensity-modulated light emitted by a transmitter. One disadvantage of such a photonic mixer device can be seen in the fact that the modulation photogates and the accumulation gates are applied on the silicon substrate, and thus restrict the optical sensor region of the photonic mixer device. Furthermore, it is not possible to generate a constant drift field in the substrate with the modulation photogates arranged on the silicon substrate.
DE 100 47 170 C2 discloses a PMD system by means of which not only the intensity but also the propagation time of an intensity-modulated light wave that is emitted by a transmitter and received by a photonic mixer device can be measured. However, the patent specification is not concerned with the realization of photonic mixer devices.
DE 198 21 974 A1 discloses a device and a method for detecting the phase and amplitude of electromagnetic waves using is photonic mixer detectors. In a manner similar to the photonic mixer detector according to DE 197 04 496 C2, modulation photogates and accumulation gates are situated on a semiconductor substrate. In contrast to the modulation photogates and accumulation gates in accordance with DE 197 04 496 C2 the modulation photogates and also accumulation gates in accordance with DE 198 21 974 A1 have the form of elongate, narrow and parallel strips.